Good question, MladenP-
Extra points are earned by doing the things that WGT wants you to do: Play a particular Blitz or course, Invite Friends, playing consecutive days, etc.
Extra points help you to increase your LEVEL, which, in turn, lets you buy better equipment (balls, clubs - etc.).
To 'buy' the better equipment, you need "CREDITS"
There are basicly, 4 ways to earn credits: 1. Watch Videos, 2. Complete 'Offers', 3. Play well enough to win points in 'free' tournaments - Stroke Play, Ready to Go's, Closest to the Hole or 4. Buy them.
So, I ask - what is it that you are trying to do - "level up" or buy better equipment?
(I will respond to your answer but my Wife just said "Dinner" and it was not a request!!)-